1992 525i Touring knock

[Tash_1991]

Ok, so i bought this touring, love it, but it's developed a knock in all of 20km. Dad and I had a quick look over, it almost sounds like a gudgeon noise. It has got warranty with it (thank god) i just wanted to know if anyone out there has experienced something similar, whether it's sedan or touring. ThanksNatasha

[ss2115]

Hi Tash.
My 1993 525i Touring has 194,000klms on it and the head came off for the first time ever just a couple of weeks ago for a small coolant crack.
My impression is they are reasonably bullet proof engines except for the occasional head crack, so any gudgeon noise or similar may be poor maintenance unfortunately.
Mines the M50 motor with Vanos.
Love the exhaust burble on these.
However, don't be hopefull about good fuel consumption - they are quite thirsty.

[Tash_1991]

Yeh but im puzzled, i've been through the books and it's been serviced religiously at Trivett Classic since new... Maybe it's just worn out...? :/ either way i'm not stressing, i love it and if it comes to it, a rebuild will happen.

[genphreak]

Yeh but im puzzled, i've been through the books and it's been serviced religiously at Trivett Classic since new... Maybe it's just worn out...? :/ either way i'm not stressing, i love it and if it comes to it, a rebuild will happen.I doubt it. These motors are made well and do not tend to wear badly- or wear very much internally really. Gudgeon pin? No way. It is not a Holden :)

I would bet, if its M50, that your plugs are not tight, or are not sealing properly as they've been removed and replaced again, after they were first installed and the one time seals compressed. That was the case when one of my M50B25s made a 'gudgeon noise' and had us all wondering what it was!

[Tash_1991]

Its actually getting new plugs as soon as i pick it up today... I thought well it could do with a bit of an overhaul before its next service... If thats the case, i'm going to be one VERY happy lady!!

[Tash_1991]

Oh and your reference to Holdens, brilliant!! Hahahaha we're at the Mount racing my boyfriends Gemini sports sedan with a mid mounted injected 186. I showed him that comment and he's like yeh, thats a totally fair call!! Hahaha i laughed.. Alot!!

[genphreak]

Oh and your reference to Holdens, brilliant!! Hahahaha we're at the Mount racing my boyfriends Gemini sports sedan with a mid mounted injected 186. I showed him that comment and he's like yeh, thats a totally fair call!! Hahaha i laughed.. Alot!!Well indeed, that was mean. I can only imagine a BMW engineer that has seen a red motor or any of those damn Buick blocks, hearing some Aussie that he or she thought a Piston was slappn' or a Gudgeon wanderin' (in their Bavarian block)- well I can only say I doubt he'd be bothering to discuss the likelihood of it happening!

But the noise sure is enough to make us think that way... lol! Glad to hear you're getting the touring! Expect to have to get new struts for the tailgate, bonnet, seats, tailgate window- they all lose their pressure. The tailgate ones are costly, I couldn't get them refilled so got them from BMA and they were like $80 each. (BTW: They have a 5 day 10% off sale on too atm).

[Tash_1991]

the tailgate ones not long got changed ;) hehe i love it, picked it up this arvo! Dad just said that if it was sparkys wouldnt it do it all the time, not just when its warm...? he has a point.. but BMW's can do weird things so who knows lol

[Tash_1991]

Just changed the plugs, KNOCK BE GONE!!!! Very happy :) thanks for the advice!!

[genphreak]

Aww and it'll go better and cleaner now to boot!

Good work! I'm jealous! It took me a while of worrying to figure that one out w mine!

FYI, best plugs are the 2-pole NGKs, followed by the Bosch 2-pole ones and then 4 pole ones, then the one pole ones... NGK are best on these motors.

[Tash_1991]

Got NGK two pole ones. Dad has a new set of genuine four pole ones, but hes keeping them for his E46 325ci lol still has an idle issue, but new plugs, throttle body and MAF clean have been a breath of fresh air to it!!! Going into the mechanic that fitted the front pads before i bought it. The pad doesnt contact half the rotor :/

[632 Regal]

If the motor is sludged up to cause the oil pickup to clog or someone ran low on oil it is possible a bearing got wasted. Not a real big project to replace but the bearings are sized to the parts, IE you need to pull the bearing to get the exact size to replace with.

[genphreak]

Not sure about how the Bendix ultimates go, but always found them hard to buy. E34 pads in Oz tend to be OE (Textar) or Bendix stock (Falcon/Commodore pads), or u can get any number of dodgey Chinese re-branded shitters. Other ceramics I have not tried, but I like the Akebono Euro ceramic ones as they are a proven and excellent match on e34 and nil/minimal dust. Are not very expensive and very easy to get from the US. Always swap the rotors for new ones at the same time, though if the rotors are looking real good as you don't drive hard on them ever then you can throw a pair of cheap pads on, blacken your wheels and half way through the normal time, replace the whole lot with the proper stuff again. Too much trouble I reckon, the parts are cheap and dodging it up risks squeals and all sorts of strife. You may have a sticky caliper though, just need to pull it off and check the piston is not rusted and the pins are not clogged up. Clean it all out, graphite it up and she's back in service with no mo' woes.

[Tash_1991]

Yes i think i've got a sticky caliper, just doesn't seem right. Worst thing dad ever did was sell the business to this clown, he is the laziest mechanic i've ever met!! He even admitted to me that the rotors were undersize, but didnt see it as a necessary thing to replace them, or tell the dealer i bought it from. Luckily said dealer is my neighbour, so i've told him about it all and the fact his stupid apprentice lost both front centre caps... I know theres nothing he can do about it, but i dont want anyone else going through the same pain in the a$$!! Where can i get the Akebono Euro ones from..?

[myles]

I'd recommend Bendix General CT pads. They're available at most local parts suppliers and they're not expensive. Very good pads for regular use, no noise, very low dust.

[Tash_1991]

Yeh i want to put a really good set in it so i can go racing XD

[genphreak]

I'd recommend Bendix General CT pads. They're available at most local parts suppliers and they're not expensive. Very good pads for regular use, no noise, very low dust.Oh cool, the CTs are half ceramic half normal so best of both worlds. If you race you want ceramics, but for day to day on the street they start to glaze a bit so need a hard stop or two every now and then to keep some bite.

I have never used the CTs. so glad to hear someone in Oz has (thanks myles) I would say they are worth trying. I've found that they are pricey or hard to find (for e34), so never have. Textars are excellent pads for street use too. Check the price and availability and decide.

I buy from BMA Auto Parts | Bumper to Bumper since 1978 | Oem auto parts, vw parts, sachs boge, mercedes benz parts, honda auto parts, saab parts (http://www.bmaparts.com), they know hoe to deal with frieght to Oz (I use std Airmail as they use the post office not couriers to deliver which can be far better if you are not always home). BMA are an attentive, caring vendor which is unusual- and they know parts better than most too ;)

[Tash_1991]

Ok cool, never looked at the BMA site, so i'll give it a go! Still not happy with how it's stopping, but i won't be taking it back there. I'm a mechanic myself, but i refuse to fix other peoples fu** ups... So if i just DIY on the weekend, then i know it's done right!!!

[genphreak]

Well as a rule of thumb, an e34 should stop

- quicker than you might think it can (though that may not be quick enough in some cases...)
- (as quick or quicker than any car its size and weight)

I know its hard to believe but it your problem is most likely a few bubbles. If the problem is force not tyre grip, a common cause is air in the brake lines, in which case, with ABS, special bleeding gear is necessary. The best way to do this is to use a hand-pump (http://www.pelicanparts.com/BMW/catalog/shopcart/BE30/POR_BE30_UPrc30_pg15.htm) to pressurise the fluid reservoir and force the fluid through the lines fast enough to bring the bubbles. No amount of foot work pumping the pedal will do it. I'd say this is your problem, an inexperienced mechanic working on these can easily allow bubbles into the lines.

More info:
http://www.pelicanparts.com/bmw/techarticles/Mult-Bleeding_Brakes/Mult-Bleeding_Brakes.htm

Other ways can work, but can also fail. Pro mechanics get foxed by these unless they have the right tools. Many just pump by foot even when they have the right tools on hand.. and many have the wrong tools for an e34!

[Tiger]

The real problem is old brake fluid... got water... which vaporize into gas and thus poor brake performance.

[genphreak]

The real problem is old brake fluid... got water... which vaporize into gas and thus poor brake performance.Unless its already been refreshed with new 'dry' fluid... however fluid is a good point- one also must remember to use Super DOT4, not just plain DOT4 'types'- not that it would make them feel bad though- not in normal driving anyhow.

[Tash_1991]

Noticed that brake dust is prominent on the rear wheels and barely on the front.. Please, correct me
if i'm wrong but it seems odd to me :/

[Tiger]

No... not odd... you just got two different brands of pads on your car. Dusty one are usually cheapo one. Even factory BMW pads are not dusty in back wheel.

Best brake pads today are Ceramic pads... Akebono makes the best.

[Tash_1991]

Yeh i thought so, but the good pads are in the rear, with el cheapo ones in the front.. Has anyone used the Brembo Max rotors?? A local parts place can get them but i've never heard of anyone using them...?